In connection with diagnosis of various diseases, such as various cancer diseases, biopsies are taken. When taking a biopsy and no malignant cells are detected, it is important that it can be ruled out that this is not simply due to that the biopsy was sampled from the wrong site. To increase the certainty of the biopsy sampling, guided biopsy may be used. Such guided biopsy sampling can be based on a number of image modalities, examples include X-ray, CT, MRI, ultrasound and optics.
For many purposes optical imaging by use of a miniaturized needle microscope is used. Imaging by use of needle microscopy has the advantage that it does not involve harmful X-rays or the expensive machinery of CT or MRI scanners. Moreover, it supports integration into the biopsy needle itself, thereby allowing direct visual inspection of the biopsy site prior to, during and after the biopsy.
In prior art, optical probe systems for medical applications scan over a field of view by means of an electromagnetically driven optical fibre system which is used to scan over a field of view. The whole field of view is scanned with a scanning frequency coinciding with a mechanical resonance frequency of the moving parts of the optical fibre system. Hereby it is possible to obtain an efficient scanning with the use of a limited drive current, thereby meaning that a reasonable scanning speed can be obtained with a limited heat dissipated by the miniature drive coils.
However, the inventor of the present invention has appreciated that in the mentioned prior art optical probe system, the scanning speed is limited by the limited scanning frequency, which again influences the time required for a sufficient scanning image—an important factor within medical applications.